Université De Sherbrooke

Quantiscript, Inc.

Eric Lavallee

Jacques Beauvais

Dominique Drouin

To fabricate masks for deep ultra-violet lithography and for extreme ultra-violet lithography, a layer of material opaque to deep ultra-violet radiation and an extreme ultra-violet radiation absorbent layer are each deposited successively with a layer of silicon and a layer of metal on a respective transparent substrate. A focused electron beam is displaced on the superposed layers of metal and silicon to form a structure of etch-resistant metal/silicon compound. The deep ultra-violet mask is then formed by etching the three layers to leave on the substrate, the metal/silicon compound structure with the extreme ultra-violet absorbent layer beneath it. The extreme ultra-violet mask is fabricated by forming the absorbent layer successively of an etch-stop sublayer, a repair buffer sublayer, and a sublayer of extreme ultra-violet radiation absorbent material, which, after etching, leaves on the substrate, the metal/silicon compound structure with the extreme ultra-violet radiation absorbent sub-layer and the repair buffer sublayer beneath it.

Method using sub-micron silicide structures formed by direct-write electron beam lithography for fabricating masks for extreme ultra-violet and deep ultra-violet lithography

A method for fabricating a sub-micron structure of etch-resistant metal/semiconductor compound on a substrate of semiconductor material comprises the step of depositing onto the substrate a layer of metal capable of reacting with the semiconductor material to form etch-resistant metal/semiconductor compound, and the step of producing a focused electron beam. The focused electron beam is applied to the layer of metal to locally heat the metal and semiconductor material and cause diffusion of the metal and semiconductor material in each other to form etch-resistant metal/semiconductor compound. The focused electron beam is displaced onto the layer of metal to form the structure of etch-resistant metal/semiconductor compound. Finally, the layer of metal is wet etched to leave on the substrate only the structure of metal/semiconductor compound. Following wet etching of the layer of metal, an oxygen plasma etch can be conducted to remove a carbon deposit formed at the surface of the structure of etch-resistant metal/semiconductor compound. Also, the substrate may be subsequently etched to remove a thin layer of metal rich semiconductor material formed at the surface of the substrate by reaction, at room temperature, of the metal and semiconductor material with each other.

Growing community of inventors

Sherbrooke, Canada

Eric Lavallee